This invention relates to franking machines for printing a postal franking on mail items.
Franking machines are provided with a print drum carrying printing elements which can be selectively set to print a desired value of postal franking and the date of franking. After setting the printing elements, printing is effected by rotating the drum and pressing an envelope or label against the drum, and the printing elements carried thereby, by means of a pressure roller. Prior to engaging the envelope, the printing elements pass through an inking station where ink is applied to the printing elements. Rotation of the drum together with the pressure roller causes the envelope to be fed therebetween and to be ejected after printing of the franking.
The printing elements, carried by the drum, for printing the franking value are set by means of thumb wheels or similar mechanical setting devices or by means of electromechanical means controlled by electrical signals located on a body of the franking machine. Mechanical linkages are provided between the mechanical setting devices, or the electromechanical means, and the printing elements to enable the printing elements to be set to print the value desired. Due to the need for rotation of the print drum and the printing elements carried thereby relative to the body of the machine, the mechanical linkages have to be constructed to set and maintain the printing elements at the desired settings while at the same time allowing rotation of the print drum. Consequently the mechanical linkages are complex and as a result are expensive to manufacture. Furthermore the linkages occupy a large space within the machine which causes difficulty in manufacturing a compact franking machine.
It is an object of the present invention to provide a construction of franking machine which is less costly to manufacture and is more compact.